Gearbox housing



FIG. 1 is an isometric view of a gearbox housing showing my new design;

FIG. 2 is a front view thereof, the shafts being shown in broken linesfor illustrative purposes;

FIG. 3 is a rear view thereof;

FIG. 4 is a side view taken from the left of FIG. 2;

FIG. 5 is a side view taken from the right of FIG. 2;

FIG. 6 is a top view thereof, the bottom being a mirror image thereof.

The ornamental design for a gearbox housing, as shown and described.